Catalytic process and apparatus



April 21, 1953 2. o. BONNER CATALYTIC PROCESS AND APPARATUS 3 snets-snee 1 Filed Aug. 31 1950 :54 CATALYTIC r R AQT R 3 a 00 1 O U r O s J. axi w 0 003. 000900 0 c n F 0 O o 0. v a 2 y m .6 2 r Y .H/ MAIN DU J Q6 J. KW) c v( JHJ, r) J k Q! C v 9 2,

T INVENTOR. 1mm ZORA D. BQ NER April 21, 1953 z. D. BONNER CATALYTIC PROCESS AND APPARATUS 3 Sheets-Shee 2 Filed Aug. 31 1950 O W MW A /un MT P 5 R O T C m R 2 m 5 0 NE W W N N m c .I o a ,I 2 H A Um 9\ w a v .INVENTOR. 20319 I). BONNER BY 977- cAC -ALYT 16 U Rllisc'ron n 124 3 Sheets-Shee 5 2. D. BONNER April 21, 1953 Filed Aug. 31, 1950 m N MN m0 3 D m 0 Z QrToRNm ouculpcr Patented Apr. 21, 1953 CATALYTIC PROCESS AND APPARATUS Zora D. Bonner, Port Arthur, Tex., assignor to Gulf Oil Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Application August 31, 1950, Serial No. 182,587

6 Claims.

This invention relates to a catalytic process and apparatus and more particularly to a method and apparatus for conducting the catalytic conversion of reactants which are of the mixed, liquid-vapor phase type.

Previous attempts to charge mixed liquid-vapor phase reactants to fixed or stationary catalytic beds have met with considerable difficulties; one of the principal problems encountered has been the diiiiculty of getting uniform distribution of liquid throughout the catalyst bed. Since in the past the reactants have generally been introduced into either the upper or lower portion of the catalyst bed through a perforated plate or grid, the result has generally been an accumulation of liquid in the catalyst bed near the entrance point of thereactants; this condition in turn has resulted in extensive coking of either the upperor lower portions of the catalyst bed. Other attempts to introduce mixed liquid-vapor phase reactants into the catalyst bed have been by means of the common perforated distribution tubes. This use, in the case of upfiow reactors, that is, reactors in which the reactants are introduced into the base or the reactor, has often run into mechanical difficulties due to the accumulation of liquid in the distribution tubes with the consequent slugging of the liquid into a single portion of the catalyst bed. In the case of downfiow reactors, that is, reactors in which the reactants are introduced into the top of the reactor, the use of a mixed liquid-vapor phase charge with the common perforated distribution tubes has often resulted in the liquid content of the charge falling to the bottom of the distribution tubes with the consequent coking of the lower portions of the catalyst bed. A still further difiiculty has occurred during the regeneration period due to the large quantities of coke in localized. areas of the catalyst bed as a result of the liquid phase cracking. This, in turn, has resulted in hot spots in the catalyst bed thus causing damage to the catalyst and often to the reactor shell.

This invention has as an object to provide a catalytic reactor in which there is a uniform distribution of liquid through a catalyst bed while charging mixed liquid-vapor phase reactants. I

An additional object is to provide for the uniform distribution of the coke iormed as a result of the reaction throughout the catalyst bed.

Another object is to provide an apparatus and process for treating a mixed liquid-vapor phase reactant in which predetermined amounts of liquid can be delivered to different portions of a catalyst bed.

A further object is to provide for a. mini= mized formation of coke in the catalyst bed.

A still further object is to provide for increased conversion of a mixed liquid-vapor phase charge to desirable reaction products.

These and other objects are accomplished by this invention which embraces a catalytic reactor comprising in combination a catalyst retaining shell, means for introducing reactants into the shell, said means for introducing reactants leading into an elongated perforated reactant distribution means positioned centrally within said shell and means at spaced intervals in said distribution means for imparting rotary motion to said reactants, and means for withdrawing the reaction products from the reactor.

This invention also provides a process for conducting a catalytic reaction which comprises passing a mixed liquid-vapor phase charge into a catalyst bed along its approximate longitudinal axis, imparting rotary motion to said charge, passing the vapor and liquid through the catalyst bed, thereby effecting the catalytic reaction and withdrawing the reaction products from the reactor.

Referring to the drawings:

Figure l is a vertical sectional view of an ups flow catalytic reactor in accordance with the in vention;

Figure 2 is a vertical sectional view of a catalytic reactor showing a method of withdrawing gealction products at the periphery of the catalyst Figure 3 is a vertical sectional view of a downflow catalytic reactor;

Figure 4 is a sectional view of a portion of the wall of a preferred form of a distributing member showing beveled perforations on the inner wall; and

Figure 5 is a fragmentary perspective view of two conic distributing members showing in detail the construction of a means for imparting rotary motion to reactants.

' My invention may best be described by refer ring to accompanying Figure 1, in which the body of catalytic reactor I0 is made up of an elongated substantially cylindrical outer shell 29 provided with heads 28 and 34 at the base and top ends respectively. The lower head 28 is provided with inlet means 38 connected to reactant distribution means M. Preheated mixed liquid-vapor phase charge is introduced through inlet means 30 and passes into reactant distribution means [4 which is made up of a succession of "upright, truncated, perforated, conic shaped members [6 which are successively smaller in average diameter from bottom to top of reactant distribution means It. The conic shaped members III referred to above have perforations IT, and the edges formed by the perforations I? and the inner walls of conic members It are beveled or chamfercd as will be described in more detail later.

The bottom of each of the conic members I5 fits closely, and is even with or slightly overlaps, but does not touch the top of the conic member immediately below. This provides a series of annular spaces which serve as discharge ports or outlets 2E3. These annular spaces or discharge ports 20 are unobstructed except for structural members I 8 which fasten the conic members It together to make up the reactant distribution means Id. The structural members It may take any appropriate form such as spacers or struts in case the reactant distribution means I4 is welded together, or bushings in case the reactant distribution means is bolted together. The structural members I8 serve to define and maintain the discharge ports 20. Set in the top of each conic member I6 are means for imparting rotary motion 22 which are shown as stationary four-bladed vanes.

Reactant distribution means I4 is embedded in a mass of granular or pellet type catalyst material I2 and extends a substantial distance into the catalyst mass or bed. The length of the reactant distribution means It in relation to the length of the catalyst mass I 2 may vary depending on the type of charge stock; however, there must be a sufiicient catalyst mass between the uppermost conic member and the outlet means 35 to effect conversion of that portion of the reactants which is distributed into the catalyst bed by the uppermost conic member.

Means for introducing gas such as hydrogen or a diluent gas comprising inlet 26 and perforated distribution ring 22 are placed in lower head 28. Drain means 32 is also placed in reactor lower head 28.

Referring to Figure 2 in which there is shown a second modification of my invention, the body of catalytic reactor .59 is made up of an elongated substantially cylindrical outer shell I9 with heads 'I2 and it at the base and top of the reactor respectively, and the lower head I2 in the base of the reactor is provided with inlet means till connected to reactant distribution means 60. r

Preheated mixed liquid-vapor phase charge is introduced through inlet means 80 and passes into reactant distribution means 6b which is made up of a succession of upright, truncated, perfo rated, conic shaped members 52 which are successively smaller in average diameter from the bottom to top of reactant distribution means I36.

The conic shaped members 52 referred to above have perforations 5 in the walls of each member and the edges formed by perforations 54 and the inner walls of the conic members 52 are beveled or chamfered as will be disclosed in more detail later. The bottom of each of the conic members 52 fits closely, and is even with or slightly overlaps, but does not touch the top of the conic member immediately below. This provides a series of annular spaces which serve as discharge ports or outlets 5B.

These annular spaces or discharge ports 56 are preferably unobstructed. except for structural members 53 which fasten the conic members 52 together to make up the reactant distribution means 69. The structural members 58 may take any appropriate form such as spacers or struts, in case the reactant distribution means 69 is welded together, or bushings in case the reactant distribution means 60 is bolted together. The structural members 53 serve to define and maintain the discharge ports 56. Set in the top of each of the conic members 52 are means for imparting rotary motion 62 which are shown as stationary four-bladed vanes.

Reactant distribution means 60 is embedded in a mass of granular or pellet type catalyst material 66 and extends a substantial distance into the catalyst mass or bed to a point near the top head 14.

Placed within reactor shell I9 and supported by structural members it] is catalyst retaining member It which takes the form of a perforated sheet of metal or a screen. The catalyst retaining member Itand the reactor shell 19 serve to define an annular space 68 about the periphery of the catalyst bed 66 which serves, together with members 84, as a means for withdrawing reaction products from the reactor. Means for introducing gases, such as hydrogen or a diluent gas comprising inlet 82 and perforated distribution ring 64, are placed in lower head 12. Drain means I8 is also placed in reactor lower head. I2.

Referring to Figure 3, the body of catalytic reactor I24 is made up of an elongated substantially cylindrical outer shell H9 provided with heads I 22 and I26 at the top and base of the reactor, respectively. The top head I22 is provided with inlet means Hill connected to reactant distribution means Hi8. Preheated mixed liquidvapor phase charge is introduced through inlet means Hill and passes into reactant distribution means I08 which is made up of a succession of elongated, perforated, cylindrical members I02 which are successively smaller in average diameter from top to bottom of reactant distribution means I08.

The cylindrical members I02 referred to above, have perforations II D, and the edges formed by the perforations III) and the inner walls of cylindrical members I22 are beveled or chamfered as will be described in more detail later.

The bottom of each of the cylindrical members I62 fits closely, and is even with or slightly overlaps but does not touch the top of the cylindrical member immediately below. This provides a series of annular spaces which serve as discharge ports or outlets I84. These annular spaces or discharge ports I04 are preferably unobstructed 6X? cept for structural members I06 which fasten the cylindrical members I 92 together to make up the reactant distribution means I68.

The structural members I66 may take any appropriate form such as spacers or struts in case the reactant distribution means I 08 is welded together, or bushings in case the reactant distribution means IE8 is bolted together. The structural members I66 serve to define and maintain discharge ports I64. Set in the top of each of the cylindrical members I02 are means for imparting rotary motion I I2 which are shown as stationary four-bladed vanes.

Reactant distribution means I68 is embedded in a mass of granular or pellet type catalyst material H6 and extends a substantial distance into the catalyst mass or bed. The length of the reactant distribution means N8 in relation to the length of the catalyst mass H6 may vary depending on the type of charge stock; however, there must be a sufficient catalyst mass between the lowermost cylindrical member and outlet means I 20 to effect conversion of that portion of the reactants which is distributed into the aosugose catalyst bed bythe lowermost cylindrical! IIIEIHP her:

E'laced= within reactor" shell I I9 and supported. by structural memhers I i-"8 catalyst retaining: member" H 4* which takes'the'tonn of a. perforated sheet of metal or a screen. Catalyst retaining. member H4 and'react'or'sheli l l-a serves-to define a space !"2-1 about the periphery and bot thin of catalyst bed I I6" which" connects tooutlet means: I20 throughwhich'the" reaction products'arawith drawn;

Referring to: Figure 4, a sectional view of enlarged portion ofit-hewallof a perrf-orated mem her is shown. The" inner edgesof perforations I! in the. inner walls. 2| of said tEIBSCOPiCIIlBHlZ- hers are beveled or chamfered forming surfaces f9. The" perforations L'F extend from surfaces I! to: outer: walls" f6 with a uniform diameter;

Referring to Figure" a fragmentary-perspec tive view is shown. of a conicmember: is with a; portion of. the. comic member l9? immediately above. The. details of structural" members f8 which, take the form of struts; or bushings are shown. Perforations liTandmeansfor imparting rotary motion" 22. which take the form in this instance of stationary four-bladed? vanes arealso shown. The pitch and/or number ofth'e blades. or vanes maybe vari'edaccording to the. amount of rotary motion or rotational velocity. desired;

The operation of the. apparatus described; can he. illustratiedlby the process. of; hydrocracking a total" petroleum crude. oil or a reduced crude m. the; apparatus. shown. in Figure I. The charge:

st'ocki together with hydrogen in amounts of; from,

1,000. to. 20,001)? s.. c. il/bbll is, preheatedi to reaction temperature whichis in. the order of; 650. to 1DDO' Blunder. a pressure. of from atmospheric. of. 1-000.

p..s..i...g,..andbeyond. Under these conditibns, .thes charge stock will take the format; amixedlliquidvapor; phase. material the, proportion; of, liquid. or

instance.

Due. to the. fact that. the. liquid, particles in the. mixed li'quidvapor phase charge; have; a. greater density; than the.- vapor, the. rotary. motion. results. in throwing\ the. liquid phase: against the-inner walls; of conic. members It; and: a por-- tion oi the. liquid phase, after contacting, and being, collected on the; inner wallsof each. conic member, is aspiratedithnough the; perforations. lz'l in. the walls of. thee conic members Itv by the vapor. phase portion. of. the charge. into catalyst bed I12 The beveled edges of. the perforations IJL (shownin detail. in Figures) tend to.-prevent the. downward flowingliquidfromaflowing aroundv the; perforations and thus. failing: to: beaspirated into the catalyst bed at this point. The? remaining. portionv of. the liquid-phase; continues; to flow downwardly along; the inner: walls: 011 the conici members and together with additional. vapor. passes-.- out: of: discharge: ports 20 at. which time it. isimmediately" contacted& by the: vapor and liquid passing: out. of the perforations: oi the conic: member immediately belowwith; the: result: that all of? the liquid portion di'spersedi uni? f'orml'y throughout" catalyst bed ii The liquid? phase tends to flow or; trickle. down;- wardly throughcatalyst bed l2; however; this tendency isopposedby the upward; motion; of the vapors and, reaction; products moving toward. outlet 31; inthe'top'oflreactor lik- Thissretention. of liquid in the catalyst: bed allowsincreased op;-

: portunity= for catalytic conversion of the liquid portion of the mixed liquid-vapor phase: re.- actant's; The" reaction products are withdrawn through: outl'et- 38 m: the. top of. reactor t0 When reactants are charged containing'a high.

1 percentage of liquid phase, or reactants are charged which contain a difiicultly convertible liquid phase; itmay not be: possible to convert all of the liquid phase into desirable reaction products; andthus pa-rt of thezliquid phase may continue to pass downwardly through the catalyst" bed collect?- in: the lower part of. the; reacton. To remoye the collected liquidl fi'omthee lower part of the reactor; and thus avoid coining this section ot the reactor;- drain means 32* has-been placed reactor base 2 8;-

Uhdei some conditions it' may be desirable;- in introduce a. hydrogen containing gas; or a diluent gas directly into the lo wer portion of thecatalyst bed I Q For this purpose; m'eansforxint'm dueing gas comprising inlet 2-6 and perforatedi distribution" ring 24 has been? provideda catalyst bed F2 mentioned: may be. any conventional hydrocracking catalyst such as ox-- ides and/or sulfides of group VI-"or group or mixtures of groups and VIII deposited on a silica-alumina on alumina carrier:

Regeneration of thecat'alyst-hed I2 is: prefers ahly' accomplished bypassing regeneration gases through inlet" means 30 and' reactant distribu- Tl'ie gasess arawithdrawn through outlet: 3 5 Although the preferred procedure for regeneration has been described1 above; it is possible to regenerate by passing regeneratibm gases into the: reactor 1a through member 3tand withdrawing said gas through reactant distributionn'reans t4 and memberwi The? operation of the apparatus showxr in Fig-*- ure 2 cam also illustrated' by the process: off hydrocracking a total p'etroieum; crude oil or a reduced crude: The charge stools tbs ether with hydrogen. in amounts of from 13000 to 20390 s"; c: fi/bh'l'. i's preheated to reaction:- temperature which: is in the order" of 650" to 1000" F. under a pressure of from" atmospheric 00 1060 pa 5. 1 g. and? beyond. Under these conditions-. the charge stoicliwill tak e the" form of a mixed liquid-vapor phase. material, theproportion' 0? liquid or" vapor phase depending on the nature of the charge stock and" the temperatureand* pressure"; l'iquiii phaseis usually distributed in the vapor phase in the form of a mist or as dropletsa This mixed. liquid-vapor phase charge is introduced into the reactant distribution means 65 within catalyst" mass 66'- a'nd catalytic reactor 5t means of inlet 'I-hemixed liquid vaporphase reactant or charge passes upwardly in reactant distribution means 610" andi contacts meansfor imparting; rotary or spinning motion 62'?- which are shown as stationary four-hladed vanes inthi's.-instance..

Due to. the? fact that the liquid particles in the mixed liquidf-vapor: phase charge have a greater density than. the vapor, the rotary motion. results in throwing; the li'quidl phase against the inner Walls of conic members 52; and a portion of the liquid phase, after contacting and being collected on the inner walls of each conic member is aspirated through the perforations 54 in the walls of the conic members 52 by the vapor phase portion of the charge into catalyst bed 66. The beveled edges of the perforations 54 (shown in detail in Figure i) tend to prevent the downward flowing liquid from flowing around the perforations and thus failing to be aspirated into the catalyst bed at this point. The remaining portion of the liquid phase continues to flow downwardly along the inner walls of the conic members, and together with additional vapor, passes out of discharge ports 55 at which time it is immediately contracted by the vapor and liquid passing out of the perforations of the conic member immediately below with the result that all of the liquid portion is dispersed uniformly throughout catalyst bed 55.

The liquid phase tends to flow or trickle downwardly through catalyst bed 66; however, the

outward or radial flow of the vapors and reac-' tion products moving radially from reactant distribution means 60 toward catalyst retaining member It, has a tendency to carry the liquid phase through catalyst bed 66 towards the periphery of the catalyst bed. This allows opportunity for conversion of the liquid portion of the mixed liquid-vapor phase reactants. The reaction products pass through catalyst retaining member 16 into the annular space 68 formed by catalyst retaining member it and reactor shell '19 and are withdrawn through outlets 84.

When reactants are charged containing a high percentage of liquid phase, or the liquid phase portion of the reactants is diflicultly convertible, it may not be possible to convert all of the liquid phase into desirable reaction products; and thus part of the liquid phase may continue to pass downwardly through the catalyst bed and collect in the lower part of the reactor. To remove the collected liquid from the lower part of the reactor, and thus avoid coking in this section of the reactor, drain means I8 has been placed in reactor base 12.

Under some conditions it may be desirable to introduce a hydrogen containing gas or a diluent gas directly into the lower portion of catalyst bed 66. For this purpose, means for introducing gas comprising inlet 82 and perforated distribution ring 64 has been provided.

The catalyst bed 66 is the sameas described for the operation of the apparatus of Figure '1;

Regeneration of the catalyst bed 66 is prefer.- ably accomplished by passing regeneration gases through means 84 into the annular space 68, through catalyst retaining member 16, and withdrawing said gases through reactant distribution means es. Although the preferred regeneration procedure has been described above,.regeneration may be accomplished by passing the regeneration gases into catalyst bed 66 by way of reactant distribution means 60 and withdrawing the regeneration gases through catalyst retaining member 7%, annular space 58 and outlets 84. r

The operation of the apparatus shown in Figure 3 may also be illustrated by' the process of hydrocracking a total petroleum crude oil or a reduced crude. The charge stock, together with hydrogen in amounts of from 1,000 to 20,000 s. c. f./bb1., is preheated to reaction temperature which is in the order of 650 to 1000 F. under a pressure of from atmospheric to 1000 p. s. i. g. and beyond. Under these conditions, the charge stock will take the form of a mixed liquid-vapor phase material, the proportion of liquid or vaporphase depending on the nature of the charge stock and the temperature and pressure. The liquid phase is usually distributed in the vapor phase in the form of a mist or as droplets. This mixed liquid-vapor phase charge is introduced into reactant distribution means I08 within catalyst mass I I6 and catalytic reactor I24 by means.

of inlet I00. The mixed liquid-vapor phase reactant or charge passes downwardly in reactant distribution means I08 and contacts means for imparting rotary or spinning motion II2 which are shown as stationary four-bladed vanes in this instance.

Due to the fact that the liquid particles in the mixed liquid-vapor phase charge have a greater density than the vapor, the rotary motion results in throwing the liquid phase. against the inner walls of cylindrical members I02; and a portion of the liquid phase, after contacting and being collected on the inner walls of each of the cylindrical members, is aspirated through the perforations II 0 in the walls of the cylindrical members I02 by the vapor phase portion of the charge into catalyst bed H6. The beveled edges of the perforations H0 (shown in more detail in Figure 4) tend to prevent the downward flowing liquid from flowing around the perforations and thus failing to be aspirated into the cata-' lystbed at this point. The remaining portion of the liquid continues to flow downwardly along the inner walls of the cylindrical members, and together with additional vapor, passes out of discharge ports I04 at which time it is immediate-.

1y contacted by the vapor and liquid passing out of the perforations of the cylindrical member immediately below with the result that all of the liquid portion is dispersed uniformly throughout catalyst bed IIB.

' The liquid phase tends to flow or trickle down wardly through catalyst bed IIB; however, since a portion of thevapors and reaction products flow outwardly perpendicular to the axis of reactant distribution means I08, a portion of the liquid phase is carried radially toward the vertical section of catalyst retaining member H4. The remaining portion of the liquid phase flows downwardly in the bed along with a portion of the vapors and reaction products to the horizontal portion ofcatalyst retaining member H4.

The reaction products and unconverted liquid are withdrawn through catalyst retaining'mem berI III, space HI and outlet I20.

The catalyst bed H6 is the same as described for the operation of the apparatus of Figure l.

Regeneration of catalyst bed H6 is preferably accomplished by passing regeneration gases through means I20 into space IZI, formed by reactor shell H9 and catalyst retaining member 4, through catalyst retaining member H4 and withdrawing the gases through reactant distribu tion means I08. Although the preferred method of regeneration has been described above, regeneration may be accomplished by introducing regeneration gases into reactant distribution means I08 and withdrawing said gases through catalyst retaining member I M, space I2I and means I20.

A desirable modification in the operation of the reactors shown in Figures 1, 2 and 3 is the use of blades or vanes comprising the means for i-mparting rotary motion of progressively increasing pitch from the inlet end of the reactant distribution means along its length with the lowest pitch'at 'theinlet end. This provides a means for imparting a low rotary motion or rotational velocity to the reactants as they enter the reactant distribution means and increases the rotary motion or rotational velocity as the reactants pass along the length of the reactant distribution means. The use of a low rotational velocity at or near the inlet prevents the distribution of an excess of liquid from the high liquid content charge into the section of the catalyst bed nearest the reactor inlet. This same effect may also be achieved by using a progressively increasing number of blades or vanes comprising the means for imparting rotational velocity from the inlet end of the reactant distribution means along its length or by increasing both the pitch and the number of blades or vanes progressively along the length of the reactant distribution means. It is further within the scope of my invention to vary the pitch and/or the number of blades or vanes comprising the means for imparting rotary motion along the length of the reactant distribution means to permit a non-uniform distribution of liquid into the catalyst bed so as to result in a predetermined pattern of liquid distribution in the catalyst bed.

The use of the apparatus of Figure 1 is desirable where there are large quantities of liquid phase presentin the charge stock to be converted as the "upflow type reactor shown in Figure 1 gives greater opportunity for conversion of the liquid portion than does the apparatus shown in Figures 2 and 3. However, the apparatus shown in Figures 2 and 3 may be used with complete satisfaction for charges which do not 2, H4 in Figure 3) and the reactor shell (19 in Figure 2, H9 in Figure 3), and withdrawn through the reactant distribution means (60 in Figure 2, 108 in Figure 3) the cool gases flow adjacent the reactor shell and the hottest gases withdrawn from the center of the catalyst bed. This has the advantage of eliminating damage to the reactor shell due to overheating.

While my invention has been described in some detail, it will be noted that there are a number of equivalents which may be used. The means for imparting rotary motion have been described vanes; however, other stationary mechanism such as a propeller shaped mechanism may be used. While the drawings indicate reactant distribution members comprising eight conic membersin Figures 1 and 2 and eight cylindrical members in Figure 3, the number of these members is not critical and may be varied with the length of thereactor or any pecularities of the charge stock. The reactant distribution means has been described as being made up of come members or cylindrical members, but it is not necessary that the reactant distribution means be made up of conic members or cylindrical members or even separate segments to fall within the sco e of m invention.

'I he process example described deals with the use of the disclosed apparatus in connection with iii hydrocracking, but the apparatus disclosed may be used to conduct any catalytic reaction in which one of the reactants or materials to be converted is partly in liquid phase, such as catalytic hydrogenation of liquid coal extracts, catalytic hydrogenation or aromatic compounds such as the conversion of benzene to cyclohexane, catalytic oxidation of acetaldehyde to acetic acid, catalytic chlorination by the direct action of chlorine gas and other reactions.

Although it is not shown in the accompanying drawing,it is within the scope of the modification of this invention shown in Figure l to use a plurality of reactant distribution members, each being similar to the single reactant distribution members indicated in the drawings.

In Figures 2 and 3 the space formed by the catalyst retaining member and the reactor shell may be replaced by other mechanism such as perforated tubing or lingers extended up the inner side of the reactor walls.

It is also within the scope of my invention to replace the downilow reactor shown in Figure 3 with an upfiow reactor in which the reactant distribution means comprising a plurality of perforated cylindrical members is inverted and the reactants are admitted into the base of the reactor and the reaction products withdrawn from the top of the reactor.

The invention described herein has the advantage of oifering a positive means for distributing the liquid portion of a mixed liquid-vapor phase charge throughout a, catalyst bed thus allowing the liquid to be more fully converted to desirable reaction products. A further desirable advantage of this invention is the prevention of the accumulation of coke in localized areas of the catalyst bed with the elimination of the resulting hot spots during regeneration and the consequent elimination of stresses and damage to the reactor and catalyst due to overheating.

During regeneration with the apparatus shown, the construction of the apparatus makes possible the handling of large quantities of regeneration gases without an excessive pressure drop across the catalyst bed. In the modifications shown in Figures 2 and 3 the coolest portion of the regeneration gases are introduced into the catalyst bed adjacent the reactor shell and the hottest portion is withdrawn from the center of the catalyst bed. Since the outlet temperature of the regeneration gases is often above 1200 F., damage occasionally occurs to the metal parts of the reactor coming in contact with the high temperature gases, and in the modifications shown in Figures 2 and '3 such damage would be confined to the reactant distribution means which can be relatively easily replaced at comparatively small expense.

The above description deals with the specific construction of the preferred modifications of the invention which have been found to satisfy all of the stated objects, but it will be understood that any changes or modifications in this design may be made by those skilled in the art without departing from the spirit of the invention as defined in the appended claims.

What I claim is:

1. Catalytic apparatus for contacting a liquidvapor mixture with a stationary bed of catalyst comprising in combination a catalyst retaining shell adapted to hold and retain a stationary bed of catalyst, an elongated hollow perforated reactant distributor positioned centrally within the shell, means for introducing liquid-vapor re- 'aeaiac'se actant into the perforated reactant distributor, means for imparting rotary motion to the liquid-vapor reactant as it passes through the perforated reactant distributorsaid means comprising a plurality of sets of stationary surfaces positioned at spaced intervals in the perforated distributor each of the surfaces in each set being at an angle to the direction-of flow of the liquidvapor reactant and cooperating to impart rotary motion to the liquid-vapor reactant and means for withdrawing reaction products from the catalyst retaining shell.

2. Catalytic apparatus for contacting a'liquidvapor mixture with a stationary bed of catalyst comprising in combination a catalyst retaining shell adapted to hold and retain a'stationarybed of catalyst, an elongated hollow perforated reactant distributor positioned centrallywithin the shell, said distributor comprising a plurality of superimposed, perforated truncated cones progressively decreasing in diameter as the top of the distributor is approached and being spaced from each-other so as to form an annular space therebetween, means for introducing liquidvapor reactant into the base of the perforated reactant distributor, means for imparting rotary motion to the liquid-vapor reactant as it passes through the perforated reactant distributor said means comprising a plurality of setsof stationary surfaces positioned at spaced intervals in the perforated distributor each of the surfaces in each set being at an angle to the direction of flow of the liquid-vapor reactant and cooperating to impart rotary motion to the liquidvapor reactant and means for withdrawing reaction products-from the-catalyst retaining shell.

3. Catalytic apparatus for-contacting a liquidvapor mixture with a stationary bed of catalyst comprising in combination a catalyst retaining shell adapted to hold and retain a stationary bed of catalyst, an elongated hollow perforated reactant distributor positioned centrally within the shell, said distributor comprising a plurality of perforated, superimposed cylinders "progres- 'sively decreasing in diameter as the lower part of the distributor is approached, means for 'introducing "liquid-vapor reactant into the top -of the perforated reactant distributor, means for imparting rotary motion to the liquid-vapor reactant as it passes "through the perforated reactant distributor said means comprising a plurality of sets of stationary surfaces positioned 'at spaced intervals in the perforated distributor each of the surfaces in each set being at an angle to the directionof flow-of the liquid-vapor reactant and cooperating to impart rotary motion to the liquid-vapor reactant and means for withdrawing reaction products from the catalyst retaining shell.

'4. A process for contacting a liquid-vapor mixture with a catalyst, which process comprises passinga streamof liquid-vapor mixture through an elongated distributing zone located in the central portion of the catalyst bed, impinging the stream of liquid-vapor mixture as it flows along the distributing zone against stationary surfaces which surfaces are set at an angle to the direction of flow of theliquid-vapor mixture, whereby rotary motion is imparted to the liquidvapor mixture as it flows through the distribut- 12 mg zone and whereby the liquid in the liquidvapor mixture is separated from the vapor before the liquid contacts the catalytic surface, introducing the so-separated liquid into the catalyst bed, passing the vapor portion of the liquidvapor charge through the catalyst bed and withdrawing reaction products from the catalyst bed.

5. Aprocess for contacting a liquid-vapor mix ture with a catalyst, which process comprises passing a stream'of liquid-vapor mixture through an elongated distributing zone located in the central portion of the catalyst bed, impinging the stream of liquid-vapor mixture as it flows along the distributing zone against stat'icnary surfaces positioned at spaced intervals in the distributing zone and set at an angle to the direction "of new of the liquid-vapor mixture whereby rotary motion is imparted to the liquidvap'or mixture as it f-lows through the "distributing "zone and whereby th liquid in the liquidvapor mixture is separated from the vapor into approximately equal portions at the spaced intervals "before the liquid contacts the catalytic surface, introducing the so-separated'liquid-por- 'tions into 'diiferent sections of the catalyst bed, passing the vapor portion of the liquid-vapor charge through the catalyst bed and withdrawing reaction products from the catalyst "bed.

6. A process of hydrocracking a hydrocarbon by contacting liquid-vapor mixture of a hydrocarbon with hydrogen and a catalyst, which process comprises passing a stream of mixed hydrocarbon liquid and vapor together with hydrogen through an elongated distributing zone located in the central portion "of the catalyst bed, impinging the stream of liquid-vapor mixture as it flows along the distributing zone against stationary surfaces, which surfaces are set at an angle to the direction of flow of the liquid-vapor mixture whereby rotary motion is imparted .to

the liquid-vapor mixture as it flows through 'the distributing zone and whereby the liquid in the liquid-vapor mixture "is separated from the vapor before the liquid contacts the catalytic surface, aspirating the so-separated liquid into the .cat-

alyst bed by passing the vapor portion of the liquid-vapor charge closely adjacent "the separated liquid and thence into the catalyst bed and withdrawing reaction products from 'the catalyst bed.

'ZORA D. BONNER.

References Cited .in the file of this patent U NITED {STATES PATENTS Great Britain Aug. 4, I889 

6. A PROCESS OF HYDROCRACKING A HYDROCARBON BY CONTACTING LIQUID-VAPOR MIXTURE OF A HYDROCARBON WITH HYDROGEN AND A CATALYST, WHICH PROCESS COMPRISES PASSING A STREAM OF MIXED HYDROCARBON LIQUID AND VAPOR TOGETHER WITH HYDROGEN THROUGH AN ELONGATED DISTRIBUTING ZONE LOCATED IN THE CENTRAL PORTION OF THE CATALYST BED, IMPINGING THE STREAM OF LIQUID-VAPOR MIXTURE AS IT FLOWS ALONG THE DISTRIBUTING ZONE AGAINST STATIONARY SURFACES, WHICH SURFACES ARE SET AT AN ANGLE TO THE DIRECTION OF FLOW OF THE LIQUID-VAPOR MIXTURE WHEREBY ROTARY MOTION IS IMPARTED TO 